The k ₀-INRIM software: a tool to compile uncertainty budgets in neutron activation analysis based on k ₀-standardisation

Abstract

A software package was developed to evaluate the uncertainty of results provided by neutron activation laboratories adopting the k 0 -standardisation method in trace elements analysis. The outputs are stand-alone and editable spreadsheet budgets based on a measurement equation including more than 40 input quantities and written to consider the effect of correlations. The program, called k 0 -INRIM, is presented to potential users and freely distributed alongside the user's manual. The measurement equation is reported and the main features are described together with the results obtained in a validation test. An uncertainty budget compiled using the software output is given as an example.

Developments of the k0-NAA measurement model implemented in k0-INRIM software

“…The measurement equation implemented in the k0-INRIM 1.0 version assumes monitor and analyte samples as pointsources counted at the same position. The efficiency ratio is modeled by the exponential of a 6-terms polynomial [5,6]:…”

“…However, it represents an easier way to deal with the partial correlation between t d a and t d m by making explicit the common part, t d m , and their difference, Δt d = t d m − t d a . Parameters that are not mentioned in this work are discussed in [5].…”

“…Among the homemade software, the k0-INRIM is an open-source computer program written in python language aimed to help NAA users to easily obtain GUM (Guide to the expression of Uncertainty in Measurement [4]) compliant uncertainty budgets while performing analysis via k 0 -standardization method [5]. Differently from k 0 software currently available, the k0-INRIM focuses on a frequently overlooked but crucial aspect of the measurement, the uncertainty evaluation.…”

The k0-INRIM software version 2.0: presentation and an analysis vademecum

“…The k0-INRIM software was developed at the Istituto Nazionale di Ricerca Metrologica (INRIM) with the aim to guide k 0 -NAA users to easily produce uncertainty budgets [5] compliant to the Guide to the expression of Uncertainty in Measurement (GUM) [6] and obtained by propagation of variances and covariances of measurement model parameters through sensitivity coefficients. However, the first version of the software lacked some functionality that might have been important to users willing to adopt this software for routine analysis in their laboratories.…”

A method to deal with correlations affecting γ counting efficiencies in analytical chemistry measurements performed by k 0-NAA

“…In previous works [11,12] we accomplished to consider correlations in the case of single-counting position setups, i.e. when sample and standard are measured at the same distance from the detector.…”